Expansion mandrel



June 26, 1928. I 1,674, 61 35 H. c. BURDEN EXPANS I ON MANDREL Filed Feb. 8, 1926 INVENTOR //ar/ 'y C Bardcn cones are drawn longitudinally within the ends of the mandrel and c hnder.

Patented June 26", 1928.

UNITED STATES" 1,674,635 PATENT OFFICE.

HARRY c. :BUannN, or mnusxr, onro, Assrenon TOJ'IEE rune AND 'rnx'rrnn MACHINERY comrm, or snNnusxY, OHIO, A conronarron 01? 01,110.

Expansion mnnnn.

Application filed February a, 1928. Serial No. 86,828.

This invention relates to expansion mandrels.

- In the paper and textile industries it is 1 common to use metallic shells or rolls for :5v various purposes such as print rolls, engraving cylinders and so forth. Such-rolls are usually surfaced with copper or like metal and when used for printing, etching, engraving and so forth, the rolls must be changed whenever a new design is to be produced. I

This invention pertains to -an expansion mandrel for use with rolls .or shells of the character specified. v The invention has for its salientobject to provide an expansion mandrel so constructed that a cylinder or shell can be easily and quickly mounted thereon or removed therefrom. Y 1

Another object of the invention is to provide an expansion mandrel that is simple in 1 construction and can be economically manufactured. i

.Further objects of the invention will appear from the following specification taken 1I1 connection with the drawin s, which in 1 form a part of this a plication, an in which Fig.1 is a longitu inal sectional elevation of an expansion mandrel constructed in accordance with the invention, a shell or cylinder being shown as mounted thereon;

Fig. 2 is an end view of one end of the device shown in Fig. 1;

Fig. 3 is a transverse. sectional elevation,

taken substantially on line 33 of Fig. 1;

Fi 4 is an end view of one end of the man rel; and

' Fig. 5 is a transverse sectlonal elevation taken through the mandrel.

The invention briefly described consists of an expansion mandrel comprisingja lurality of radially disposed sectors. ac of these sectors is integrally-connected 'to ,the

. adjacent sectors, being connected to one adjacent sector at the outer periphery of the sector and being connected to the other adjacent sector at the inner periphery thereof. The sectors are provided at their ends with conical surfaces adapted to coact with cones formed on the mandrel shaft so that as these ner surface of the cylinder or roll. Further details'of the invention will appear from the following description.

Inthe embodiment of the invention illustrated in the drawings, theexpansible. mandrel comprises a plurality of sectors A, B, C, D E and F radially disposed and having inner peripheral surfaces 10 and outer peri heral surfaces 11. The mandrel is pre erably formed of some metal relatively ight inweight such as aluminum and may be formed by casting or in any other desired manner.-

From the showing particularly in Fig. 5

it will be noted that all of, the sectors of -,the mandrel are integrally connected; for

instance, sector A is connected at its lnner perlphery 10 to the inner periphery 10 of the sector B and sector A .is connected at its outer periphe 11 to the outer periphery F This form of construc' 11 ofthe sector tion as will be seen from Fig. 5, results in producing a series of radial slots 15 and 16, the slots 15 extending inwardly from the outer periphe 11 of the sectors to the inner periprhery 10 t ereof and the slots 16 extendg om the inner periphery 10 to the outer periphery 11 thereof.

T are substantiall cylindrical as shown at 18 at the central ongitudinal portions of the sectors but the inner peripheries at the. two

ends of the sectors are conical as shown at 20 and 21. Attention is called to the fact that the cone 20 is larger than the cone 21, the smaller end of the cone 20 being slightly larger than the larger end of the cone 21.

The e ansion mandrel as shown in Figs. 1 and 3 1s adapted to receive on' its outer "surface a shell or cylinder 25 formed of any suitable metal such ascopper, or brass and the mandrel is mounted on a shaft 28 having. formed thereon or secured thereto a pair of cones 30 and 31 ada ted-to be received by the cones 20 and 21 ormed on the mandrel and to expand the mandrel as the cones 30 and '31 are drawn into the mandrel.

' i The shaft 28 is threaded adjacent the ends thereof-as shown at 32 and 33 and nuts 34' and 35 are mounted on the threaded pore inner peripheries 10 of the sectors tions' 32 and 33. Heads or covers 40 and d1 are mounted between the nuts 35 and the When a shell or cylinder is to be mounted on a mandrel, it is slipped onto. the mandrel and the shaft 28 is then drawn into the mandrel by rotating the nut which causes the cones 30 and 31 to be drawn into the conical openings 20 and 21. When the mandrel has been expanded into firm, gripping engagement with the inner surface of the cylinder 25, the nut 34 is rotated to cause the end cover or head to close the left hand end of the cylinder (viewing Fig. 1) and to lockthe mandrel in the cylinder.

In order to prevent relative rotation between the mandrel and the shaft, keys and 46 are mounted in keyways in the cones 30 and 31 and engage keywa ys 47 and 48 formed in the inner peripheries of the mandrel sectors.

1n order to prevent relative rotation be-- tween the mandrel and the cylinder or drum 25, keys 50 are interposed between the outer periphery of the sectors as shown at 51 and the inner periphery of the drum.

From the foregoing description it will be seen that a simple and practical mandrel construction has been designed and that by the use of this mandrel, cylinders can be easily and quickly mounted thereon and removed therefrom.

Although one specific embodiment of the invention has been particularly shown and described, it will be understood that the in vention is capable of modification and that changes in the construction and in the arrangement of the various cooperating parts may be made without departing from thespirit or scope of the invention, as expressed in the following claims.

What I claim is: 4

1. 'An expansion mandrel comprising a plurality of circumferentially arranged sectors, each sector being integrally connected at its inner periphery to one adjacent sector and at its outer periphery to the other ad jacent sector. I

2. An expansion mandrel comprisin a plurality of circumferentially arranged idollow sectors having outer surfaces forming a cylindrical surface and having inner surfaces forminga conical surface, said sectors being integrally connected together.

3. An expansion mandrel having an inner 'wall and an outer wall and portions connecting said inner and outer walls, the inner wall being interrupted by a plurality of out wardly extending slots and the outer wall being interrupted by a pluralityof inwardly extending slots.

4. An expansidn mandrel comprising a plurality of circumferentially arranged expansible sections, each-section having inner and outer arcuate walls, the inner wall of each section being integrally connected. to the section on one side thereof and the outer wall of each section being connected to the section on the other side thereof.

5. An expansion mandrel comprising a plurality of circumferentially arranged expansible sections, each section having inner and outer arcuate walls, the inner wall of' each section being integrally connected to' the section on one side thereof and the outer' wall of each section being'connected t0 the section on the other side thereof, the inner walls of said sectionsforming a conical surface and the outer walls of the sections form'- inging a cylindrical surface.

6. In combination, an expansion mandrel comprising a plurality of circumferentially arranged sectors having outer surfaces to gether forming a cylindrical surface and having inner surfaces together forming a plurality of conical surfaces, said sections being integrally connected together, and a mandrel shaft having a plurality of cones;

formed thereon adapted to enter the conical inner surfaces of the mandrel and expand the mandrel. t

7. A one piece expansion mandrel comprising a plurality of circumferentiallvarranged, hollow sectors having outer surfaces integrally connected to- 

